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a(n) = phi(n)_phi(n) where phi() = A000010.
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%I #15 Jul 04 2022 12:18:31

%S 1,1,2,2,4,2,6,4,6,4,10,4,14,6,8,8,22,6,26,8,14,10,46,8,40,14,26,14,

%T 64,8,90,22,40,22,52,14,114,26,52,22,160,14,170,40,52,46,190,22,170,

%U 40,98,52,262,26,160,52,114,64,298,22,360,90,114,98,200,40,402,98,180,52,490

%N a(n) = phi(n)_phi(n) where phi() = A000010.

%C See A122618 for notation.

%H Antti Karttunen, <a href="/A122645/b122645.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A122618(A000010(n)). - _Antti Karttunen_, Dec 05 2017

%p a:= n-> (b-> (l-> add(l[i]*b^(i-1), i=1..nops(l)))(

%p convert(b, base, 10)))(numtheory[phi](n)):

%p seq(a(n), n=1..80); # _Alois P. Heinz_, Jul 04 2022

%o (PARI)

%o A122618(n, d=digits(n)) = d*vectorv(#d, i, n^(#d-i)); \\ _M. F. Hasler_, Apr 22 2015

%o A122645(n) = A122618(eulerphi(n)); \\ _Antti Karttunen_, Dec 05 2017

%Y Cf. A000010, A122618.

%K nonn,base,look

%O 1,3

%A _N. J. A. Sloane_, Sep 21 2006